\argremovecomment #1\comment\ArgTerm%  }%}% First remove any @comment, then any @c comment.\def\argremovecomment#1\comment#2\ArgTerm{\argremovec #1\c\ArgTerm}\def\argremovec#1\c#2\ArgTerm{\argcheckspaces#1\^^M\ArgTerm}% Each occurence of `\^^M' or `<space>\^^M' is replaced by a single space.%% \argremovec might leave us with trailing space, e.g.,%    @end itemize  @c foo% This space token undergoes the same procedure and is eventually removed% by \finishparsearg.%\def\argcheckspaces#1\^^M{\argcheckspacesX#1\^^M \^^M}\def\argcheckspacesX#1 \^^M{\argcheckspacesY#1\^^M}\def\argcheckspacesY#1\^^M#2\^^M#3\ArgTerm{%  \def\temp{#3}%  \ifx\temp\empty    % We cannot use \next here, as it holds the macro to run;    % thus we reuse \temp.    \let\temp\finishparsearg  \else    \let\temp\argcheckspaces  \fi  % Put the space token in:  \temp#1 #3\ArgTerm}% If a _delimited_ argument is enclosed in braces, they get stripped; so% to get _exactly_ the rest of the line, we had to prevent such situation.% We prepended an \empty token at the very beginning and we expand it now,% just before passing the control to \next.% (Similarily, we have to think about #3 of \argcheckspacesY above: it is% either the null string, or it ends with \^^M---thus there is no danger% that a pair of braces would be stripped.%% But first, we have to remove the trailing space token.%\def\finishparsearg#1 \ArgTerm{\expandafter\next\expandafter{#1}}% \parseargdef\foo{...}%	is roughly equivalent to% \def\foo{\parsearg\Xfoo}% \def\Xfoo#1{...}%% Actually, I use \csname\string\foo\endcsname, ie. \\foo, as it is my% favourite TeX trick.  --kasal, 16nov03\def\parseargdef#1{%  \expandafter \doparseargdef \csname\string#1\endcsname #1%}\def\doparseargdef#1#2{%  \def#2{\parsearg#1}%  \def#1##1%}% Several utility definitions with active space:{  \obeyspaces  \gdef\obeyedspace{ }  % Make each space character in the input produce a normal interword  % space in the output.  Don't allow a line break at this space, as this  % is used only in environments like @example, where each line of input  % should produce a line of output anyway.  %  \gdef\sepspaces{\obeyspaces\let =\tie}  % If an index command is used in an @example environment, any spaces  % therein should become regular spaces in the raw index file, not the  % expansion of \tie (\leavevmode \penalty \@M \ ).  \gdef\unsepspaces{\let =\space}}\def\flushcr{\ifx\par\lisppar \def\next##1{}\else \let\next=\relax \fi \next}% Define the framework for environments in texinfo.tex.  It's used like this:%%   \envdef\foo{...}%   \def\Efoo{...}%% It's the responsibility of \envdef to insert \begingroup before the% actual body; @end closes the group after calling \Efoo.  \envdef also% defines \thisenv, so the current environment is known; @end checks% whether the environment name matches.  The \checkenv macro can also be% used to check whether the current environment is the one expected.%% Non-false conditionals (@iftex, @ifset) don't fit into this, so they% are not treated as enviroments; they don't open a group.  (The% implementation of @end takes care not to call \endgroup in this% special case.)% At runtime, environments start with this:\def\startenvironment#1{\begingroup\def\thisenv{#1}}% initialize\let\thisenv\empty% ... but they get defined via ``\envdef\foo{...}'':\long\def\envdef#1#2{\def#1{\startenvironment#1#2}}\def\envparseargdef#1#2{\parseargdef#1{\startenvironment#1#2}}% Check whether we're in the right environment:\def\checkenv#1{%  \def\temp{#1}%  \ifx\thisenv\temp  \else    \badenverr  \fi}% Evironment mismatch, #1 expected:\def\badenverr{%  \errhelp = \EMsimple  \errmessage{This command can appear only \inenvironment\temp,    not \inenvironment\thisenv}%}\def\inenvironment#1{%  \ifx#1\empty    out of any environment%  \else    in environment \expandafter\string#1%  \fi}% @end foo executes the definition of \Efoo.% But first, it executes a specialized version of \checkenv%\parseargdef\end{%  \if 1\csname iscond.#1\endcsname  \else    % The general wording of \badenverr may not be ideal, but... --kasal, 06nov03    \expandafter\checkenv\csname#1\endcsname    \csname E#1\endcsname    \endgroup  \fi}\newhelp\EMsimple{Press RETURN to continue.}%% Simple single-character @ commands% @@ prints an @% Kludge this until the fonts are right (grr).\def\@{{\tt\char64}}% This is turned off because it was never documented% and you can use @w{...} around a quote to suppress ligatures.%% Define @` and @' to be the same as ` and '%% but suppressing ligatures.%\def\`{{`}}%\def\'{{'}}% Used to generate quoted braces.\def\mylbrace {{\tt\char123}}\def\myrbrace {{\tt\char125}}\let\{=\mylbrace\let\}=\myrbrace\begingroup  % Definitions to produce \{ and \} commands for indices,  % and @{ and @} for the aux file.  \catcode`\{ = \other \catcode`\} = \other  \catcode`\[ = 1 \catcode`\] = 2  \catcode`\! = 0 \catcode`\\ = \other  !gdef!lbracecmd[\{]%  !gdef!rbracecmd[\}]%  !gdef!lbraceatcmd[@{]%  !gdef!rbraceatcmd[@}]%!endgroup% @comma{} to avoid , parsing problems.\let\comma = ,% Accents: @, @dotaccent @ringaccent @ubaraccent @udotaccent% Others are defined by plain TeX: @` @' @" @^ @~ @= @u @v @H.\let\, = \c\let\dotaccent = \.\def\ringaccent#1{{\accent23 #1}}\let\tieaccent = \t\let\ubaraccent = \b\let\udotaccent = \d% Other special characters: @questiondown @exclamdown @ordf @ordm% Plain TeX defines: @AA @AE @O @OE @L (plus lowercase versions) @ss.\def\questiondown{?`}\def\exclamdown{!`}\def\ordf{\leavevmode\raise1ex\hbox{\selectfonts\lllsize \underbar{a}}}\def\ordm{\leavevmode\raise1ex\hbox{\selectfonts\lllsize \underbar{o}}}% Dotless i and dotless j, used for accents.\def\imacro{i}\def\jmacro{j}\def\dotless#1{%  \def\temp{#1}%  \ifx\temp\imacro \ptexi  \else\ifx\temp\jmacro \j  \else \errmessage{@dotless can be used only with i or j}%  \fi\fi}% The \TeX{} logo, as in plain, but resetting the spacing so that a% period following counts as ending a sentence.  (Idea found in latex.)%\edef\TeX{\TeX \spacefactor=1000 }% @LaTeX{} logo.  Not quite the same results as the definition in% latex.ltx, since we use a different font for the raised A; it's most% convenient for us to use an explicitly smaller font, rather than using% the \scriptstyle font (since we don't reset \scriptstyle and% \scriptscriptstyle).%\def\LaTeX{%  L\kern-.36em  {\setbox0=\hbox{T}%   \vbox to \ht0{\hbox{\selectfonts\lllsize A}\vss}}%  \kern-.15em  \TeX}% Be sure we're in horizontal mode when doing a tie, since we make space% equivalent to this in @example-like environments. Otherwise, a space% at the beginning of a line will start with \penalty -- and% since \penalty is valid in vertical mode, we'd end up putting the% penalty on the vertical list instead of in the new paragraph.{\catcode`@ = 11 % Avoid using \@M directly, because that causes trouble % if the definition is written into an index file. \global\let\tiepenalty = \@M \gdef\tie{\leavevmode\penalty\tiepenalty\ }}% @: forces normal size whitespace following.\def\:{\spacefactor=1000 }% @* forces a line break.\def\*{\hfil\break\hbox{}\ignorespaces}% @/ allows a line break.\let\/=\allowbreak% @. is an end-of-sentence period.\def\.{.\spacefactor=3000 }% @! is an end-of-sentence bang.\def\!{!\spacefactor=3000 }% @? is an end-of-sentence query.\def\?{?\spacefactor=3000 }% @w prevents a word break.  Without the \leavevmode, @w at the% beginning of a paragraph, when TeX is still in vertical mode, would% produce a whole line of output instead of starting the paragraph.\def\w#1{\leavevmode\hbox{#1}}% @group ... @end group forces ... to be all on one page, by enclosing% it in a TeX vbox.  We use \vtop instead of \vbox to construct the box% to keep its height that of a normal line.  According to the rules for% \topskip (p.114 of the TeXbook), the glue inserted is% max (\topskip - \ht (first item), 0).  If that height is large,% therefore, no glue is inserted, and the space between the headline and% the text is small, which looks bad.%% Another complication is that the group might be very large.  This can% cause the glue on the previous page to be unduly stretched, because it% does not have much material.  In this case, it's better to add an% explicit \vfill so that the extra space is at the bottom.  The% threshold for doing this is if the group is more than \vfilllimit% percent of a page (\vfilllimit can be changed inside of @tex).%\newbox\groupbox\def\vfilllimit{0.7}%\envdef\group{%  \ifnum\catcode`\^^M=\active \else    \errhelp = \groupinvalidhelp    \errmessage{@group invalid in context where filling is enabled}%  \fi  \startsavinginserts  %  \setbox\groupbox = \vtop\bgroup    % Do @comment since we are called inside an environment such as    % @example, where each end-of-line in the input causes an    % end-of-line in the output.  We don't want the end-of-line after    % the `@group' to put extra space in the output.  Since @group    % should appear on a line by itself (according to the Texinfo    % manual), we don't worry about eating any user text.    \comment}%% The \vtop produces a box with normal height and large depth; thus, TeX puts% \baselineskip glue before it, and (when the next line of text is done)% \lineskip glue after it.  Thus, space below is not quite equal to space% above.  But it's pretty close.\def\Egroup{%    % To get correct interline space between the last line of the group    % and the first line afterwards, we have to propagate \prevdepth.    \endgraf % Not \par, as it may have been set to \lisppar.    \global\dimen1 = \prevdepth  \egroup           % End the \vtop.  % \dimen0 is the vertical size of the group's box.  \dimen0 = \ht\groupbox  \advance\dimen0 by \dp\groupbox  % \dimen2 is how much space is left on the page (more or less).  \dimen2 = \pageheight   \advance\dimen2 by -\pagetotal  % if the group doesn't fit on the current page, and it's a big big  % group, force a page break.  \ifdim \dimen0 > \dimen2    \ifdim \pagetotal < \vfilllimit\pageheight      \page    \fi  \fi  \box\groupbox  \prevdepth = \dimen1  \checkinserts}%% TeX puts in an \escapechar (i.e., `@') at the beginning of the help% message, so this ends up printing `@group can only ...'.%\newhelp\groupinvalidhelp{%group can only be used in environments such as @example,^^J%where each line of input produces a line of output.}% @need space-in-mils% forces a page break if there is not space-in-mils remaining.\newdimen\mil  \mil=0.001in% Old definition--didn't work.%\parseargdef\need{\par %%% This method tries to make TeX break the page naturally%% if the depth of the box does not fit.%{\baselineskip=0pt%%\vtop to #1\mil{\vfil}\kern -#1\mil\nobreak%\prevdepth=-1000pt%}}\parseargdef\need{%  % Ensure vertical mode, so we don't make a big box in the middle of a  % paragraph.  \par  %  % If the @need value is less than one line space, it's useless.  \dimen0 = #1\mil  \dimen2 = \ht\strutbox  \advance\dimen2 by \dp\strutbox  \ifdim\dimen0 > \dimen2    %    % Do a \strut just to make the height of this box be normal, so the    % normal leading is inserted relative to the preceding line.    % And a page break here is fine.    \vtop to #1\mil{\strut\vfil}%    %    % TeX does not even consider page breaks if a penalty added to the    % main vertical list is 10000 or more.  But in order to see if the    % empty box we just added fits on the page, we must make it consider    % page breaks.  On the other hand, we don't want to actually break the    % page after the empty box.  So we use a penalty of 9999.    %    % There is an extremely small chance that TeX will actually break the    % page at this \penalty, if there are no other feasible breakpoints in    % sight.  (If the user is using lots of big @group commands, which    % almost-but-not-quite fill up a page, TeX will have a hard time doing    % good page breaking, for example.)  However, I could not construct an    % example where a page broke at this \penalty; if it happens in a real    % document, then we can reconsider our strategy.    \penalty9999    %    % Back up by the size of the box, whether we did a page break or not.    \kern -#1\mil    %    % Do not allow a page break right after this kern.    \nobreak  \fi}% @br   forces paragraph break (and is undocumented).\let\br = \par% @page forces the start of a new page.%\def\page{\par\vfill\supereject}% @exdent text....% outputs text on separate line in roman font, starting at standard page margin% This records the amount of indent in the innermost environment.% That's how much \exdent should take out.\newskip\exdentamount% This defn is used inside fill environments such as @defun.\parseargdef\exdent{\hfil\break\hbox{\kern -\exdentamount{\rm#1}}\hfil\break}% This defn is used inside nofill environments such as @example.\parseargdef\nofillexdent{{\advance \leftskip by -\exdentamount  \leftline{\hskip\leftskip{\rm#1}}}}% @inmargin{WHICH}{TEXT} puts TEXT in the WHICH margin next to the current% paragraph.  For more general purposes, use the \margin insertion% class.  WHICH is `l' or `r'.